Method and device for controlling beginning point of optical pick-up unit

Abstract

A method and device are provided for controlling movement of an optical pick-up unit. The method includes a) moving the optical pick-up unit toward a target position of an optical disc; b) while the optical pick-up unit is in motion, detecting a load voltage of a driver for moving the optical pick-up unit and detecting a counted value of the driver's output pulses generated as the driver is activated; and c) determining whether the optical pick-up unit having been moved is positioned at a beginning point of the optical disc on the basis of a current load voltage of the driver and the counted value of the drive's output pulses.

1 . A method for controlling movement of an optical pick-up unit, comprising: 
 a) moving the optical pick-up unit toward a target position of an optical disc;    b) while the optical pick-up unit is in motion, detecting a load voltage of a driver for moving the optical pick-up unit and detecting a counted value of the driver's output pulses generated as the driver is activated; and    c) determining whether the optical pick-up unit having been moved is positioned at a beginning point of the optical disc on the basis of a current load voltage of the driver and the counted value of the drive's output pulses.    
   
   
       2 . The method as set forth in  claim 1 , wherein the step (c) includes: 
 Cl) comparing the current load voltage of the driver with a prescribed load voltage to determine whether the optical pick-up unit is positioned at the beginning point of the optical disc.    
   
   
       3 . The method as set forth in  claim 1 , wherein the beginning point of the optical disc is an innermost data track of the optical disc.  
   
   
       4 . The method as set forth in  claim 1 , further comprising: 
 d) if the optical pick-up unit has moved to the beginning point of the optical disc, performing a servo-tuning operation.    
   
   
       5 . The method as set forth in  claim 1 , wherein in the step (b), the driver's output pulses are step pulses generated from a rotation of a sled motor being the driver.  
   
   
       6 . A device for controlling movement of an optical pick-up unit, comprising: 
 first means for moving the optical pick-up unit toward a target position of an optical disc;    while the optical pick-up unit is in motion, second means for detecting a load voltage of a driver for moving the optical pick-up unit and detecting a counted value of the driver's output pulses generated as the driver is activated; and    third means for determining whether the optical pick-up unit having been moved is positioned at a beginning point of the optical disc on the basis of a current load voltage of the driver and the counted value of the drive's output pulses.    
   
   
       7 . The device as set forth in  claim 6 , wherein the third means compares the current load voltage of the driver with a prescribed load voltage to determine whether the optical pick-up unit is positioned at the beginning point of the optical disc.  
   
   
       8 . The device as set forth in  claim 6 , wherein the beginning point of the optical disc is an innermost data track of the optical disc.  
   
   
       9 . The device as set forth in  claim 6 , further comprising: 
 fourth means for performing a servo-tuning operation if the optical pick-up unit has moved to the beginning point of the optical disc.    
   
   
       10 . The device as set forth in  claim 6 , wherein the driver's output pulses are step pulses generated from a rotation of a sled motor being the driver.